Re: [Harp-L] RE: Suzuki Welded Reed/00-90 screws

["Vern Smith" <jevern@xxxxxxx>]

----- Original Message ----- 
From: "Joe and Cass Leone" <leone@xxxxxxxx>
To: "Harvey Berman" <cscharp@xxxxxxxxxxxxx>
Cc: <harp-l@xxxxxxxxxx>
Sent: Friday, October 10, 2008 10:35 AM
Subject: Re: [Harp-L] RE: Suzuki Welded Reed/00-90 screws


> On Oct 10, 2008, at 2:07 AM, Harvey Berman wrote:
>
> >  My problem is that the  hole is not centered in the slot.  It is offset 
> > .0045 in. to the  right.  It looks like all the welds on my Suzuki are 
> > done the same  way.  I do not understand why they did that.
>
> I don't think it was intentional. I believe that the tooling jig is 
> showing wear.

I agree that it wasn't intentional.

However, punch/die wear doesn't change the locations of the holes and slots 
relative to each other.  The edges of the holes and slots begin to develop 
burrs and tears as the square, sharp edges of the tools round off.

If all of the holes are off the slot centerlines by the same amount, it is 
probable that they used different punches for the slots and the holes. The 
registration of the part in the punching machines was not the same from one 
operation to the other.

Adding the round holes was probably an afterthought when the problem of reed 
raplacement arose.  Rather than re-make the existing plate inventory, they 
made punches with just the round holes and reworked the existing plates. 
Thus the off-center holes arose from a registration error in the machine.  I 
don't know but it's just my guess.  This scenario is consistent with the 
hole-position error that you describe.

IMO, the best remedy is to "stretch" the holes in the reeds with a needle 
file to allow them to line up with the slot.  Then you can moderately 
tighten the screw/nut and "walk" the reed onto alignment tapping on its 
base.  I think that "walking" the reed sideways without any clearance in the 
hole would be very difficult because somewhere, metal has to distort.

Vern